Barracuda Challenger Forum

Author Topic: Holley Carb Dies When Foot on the Gas....  (Read 587 times)

Offline cv70chall

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  • 1970 Challenger
Re: Holley Carb Dies When Foot on the Gas....
« Reply #15 on: April 12, 2017 - 10:36:41 AM »
440 Auto/ 727
Comp Cam .477 lift
2450 RPM @ 60MPH
489 casing/ sure-grip 3:23 gears
Idle set at 950RPM
Actually had to retard the timing as it was so advanced, it was actually causing combustion in the exhaust manifolds and incredible heat. All normal now.

Anything I can do? It's more tempermental when cold- naturally...




Offline Chryco Psycho

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #16 on: April 12, 2017 - 11:47:19 AM »
It can be low fuel level in the bowl also you ned to work through the entire tuning process .I wrote a guide in the archives section

Challenger - You`ll wish You Hadn`t

Offline 734406pk

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #17 on: April 12, 2017 - 08:46:34 PM »
Where's the dif tag located?
I don't have a build sheet. (No fender tag  :dunno:)
Also I can't take it to 60mph since its not registered yet. I just got it and was driving it around the block.

The ratio tag should be attached under one of the nuts that attach the differential to the axle housing. It might be gone by now, not that important. 1973 was an emissions year and the rear axle ratios where usually numerically low as in 2.73 etc. This can make the carb difficult to tune. What is the specs on the cam that you are running?
« Last Edit: April 12, 2017 - 08:50:48 PM by 734406pk »
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive


Offline 734406pk

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #18 on: April 12, 2017 - 08:53:28 PM »
440 Auto/ 727
Comp Cam .477 lift
2450 RPM @ 60MPH
489 casing/ sure-grip 3:23 gears
Idle set at 950RPM
Actually had to retard the timing as it was so advanced, it was actually causing combustion in the exhaust manifolds and incredible heat. All normal now.

Anything I can do? It's more tempermental when cold- naturally...


Do you know the duration on your Comp .477" lift cam? Do you have the resources to do a full tune one this 440 (with instructions of course)?
Carb tuning:::
http://www.cuda-challenger.com/cc/index.php?topic=822.0
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline 72and86

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #19 on: April 13, 2017 - 12:42:06 AM »
Do you know the duration on your Comp .477" lift cam? Do you have the resources to do a full tune one this 440 (with instructions of course)?
Carb tuning:::
http://www.cuda-challenger.com/cc/index.php?topic=822.0


All I know is what Ive told you already. Anything inside the motor, I have no idea. I'm new to this party. I'll check out that link though... thank you Steve

Offline xtopfuel

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #20 on: April 13, 2017 - 05:28:18 AM »
since you don't know about the internals which is quite understandable I would suggest you start with timing and set on point, check the accel pump as stated above by checking the timing of fuel out of nozzles when cracking the throttle, if you are capable check the float height to be sure, if trouble arises have a proper carb shop go through the carb and make sure they have a flow bench

Offline 73_Cuda_4_Me

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #21 on: April 13, 2017 - 08:24:43 AM »
You say you had to retard the timing, but did it have stumble before you did that?

it may be that you get too much advance if it's a stock distributor...

If you are running vacuum advance in addition, you'll get even more changes that can be hard to compensate for.

Non-stock cams like advance (18-20 degrees at idle), but when stock dizzy goes through mechanical advance curve, you end up with 40-50 degrees at higher rpm, and another 10-15 in vacuum advance.

As Chryco would say, start by disconnecting vacuum advance, setting initial timing to what cam likes, see how it runs, and check where final timing comes out at... should have no more than 34-36 at full (all in around 3000/3500 rpm).

If you get too much, you may need to add advance limiter plate or switch to newer dizzy that lets you set total amount of advance...
1973 Plymouth Cuda BS23H3B567783

R11 V6X EN2
M21 M25 M31 M88 N41 N42
V1X U B41 C56 G37 J54
JY9 A6X9 0 703 501616
E55 D34 BS23 H3B 567783

Offline 734406pk

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #22 on: April 13, 2017 - 09:02:36 PM »
We have 2 members posting Holley carb questions, 72and86  with a 340 & CV70Chall with a 440. CV70Chall-  start a new thread to save confusion.  :2thumbs:
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline xtopfuel

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #23 on: April 14, 2017 - 06:01:36 AM »
 :iagree:

Offline 72and86

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #24 on: April 14, 2017 - 12:54:23 PM »
since you don't know about the internals which is quite understandable I would suggest you start with timing and set on point, check the accel pump as stated above by checking the timing of fuel out of nozzles when cracking the throttle, if you are capable check the float height to be sure, if trouble arises have a proper carb shop go through the carb and make sure they have a flow bench

Ok. Hopefully work on the carb this weekend when the new jets arrive.
What should the timing be? (Ive never done this so hopefully my older mechanic friend will help me.  :bigsmile:)

Offline xtopfuel

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #25 on: April 14, 2017 - 07:13:11 PM »
You have a 340 yes

Offline xtopfuel

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #26 on: April 14, 2017 - 07:15:55 PM »
I like to set total mechanical only the hell with base timing at around 2000rpm set to 35-36 should work well

Offline 72and86

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #27 on: April 14, 2017 - 07:28:57 PM »
I like to set total mechanical only the hell with base timing at around 2000rpm set to 35-36 should work well

Ok thanks.

Offline 72and86

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #28 on: April 18, 2017 - 01:26:06 PM »
Thanks to everyone for your help.
With the help of my mechanic friend, we swapped out the 65 nozzles and replaced them with 68s. He adjusted the timing to 3 TDC and the car runs awesome now. No hesitation.

As Ed China would say "Job done."

Offline xtopfuel

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Re: Holley Carb Dies When Foot on the Gas....
« Reply #29 on: April 18, 2017 - 03:37:16 PM »
Congrats